How Do Astronauts Log Their Flight Hours?

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Do we log our time in space in an airplane-style logbook? Nope, not really, but our time in space is “logged” by the good folks on the ground. When I returned to Earth following my stint as flight engineer on board the International Space Station, my lead flight director, Robert Dempsey (aka Dr. Astronomy) was ready to provide me with my on-orbit statistics. He casually told me I had been in space 151 days, 18 hours, 23 minutes, and 14 seconds. Among friends we round up—astronauts like higher numbers—to 152 days. He did point out that he gave me credit for the time it took the shuttle Atlantis to reach the unofficial “astronaut international” altitude limit of 100 km or 62.1 nautical miles—measured from the sea level anchor of Kennedy Space Center’s launch pad 39A to the imaginary threshold at our atmosphere’s edge. I am assuming this is standard practice when NASA determines astronaut in-space flight times.

While flying the T-38, many of the instructor pilots would offer to sign our civilian general aviation log books (for those of us who had our flight certificates), allowing us to document our NASA-modified Air Force trainer flight time for future reference. I never took them up on it, and I’m not sure how the hours were logged by my military astronaut colleagues. It seemed too difficult a process with regard to filling out Federal Aviation Administration paperwork in hopes (no guarantees) of receiving actual credit for the flight hours. I assume though, that some of my colleagues did. Some of my Penguin classmates were certified flight instructors, and perhaps those hours helped them to future flying goals.

I received a printout from the meticulous and now-retired Mavis Ilkenhans (she tracked all of this data electronically) when I retired in January 2013 that showed:

Simulator hours: 6.60 (T-38)

Actual instrument hours: 828.60 (T-38 and GA)

Simulated instrument hours: 7.70 (T-38)

Night hours: 741.90 (all)

Total flight hours: 1,469

These hours included my time as a mission specialist and co-pilot in the KSC 135 (zero-G airplane), the shuttle training aircraft, the space shuttles Atlantis and Discovery, the shuttle carrier aircraft, and first-pilot time in three general aviation aircraft (Cessna 172/150, Piper Archer-28). I also got credit for 0.1 hours of first-pilot time in the T-38 when I was allowed to perform a touch and go from the backseat.

I would end up logging about 167 days in outer space, grateful for two forays above our atmosphere, and nearly 40 hours of spacewalking time spread over six spacewalks. Those numbers work just fine for me. They’re easy to remember and they make me very proud!